Detection of hepatocyte growth factor in oral rinses using water for possible periodontal diagnosis.

The aim of this study is to analyze the relationship between Hepatocyte Growth Factor (HGF) levels in oral rinses using water and clinical parameters of periodontitis; and furthermore, to evaluate the potential of a prototype HGF immunochromatographic paper test strip (HGF-TS) for screening of periodontitis, in comparison with a commercially-available occult blood (hemoglobin) test strip (Hb-TS). Clinical periodontal parameters were recorded, and oral rinses were collected, from 125 subjects. Then, the presence of HGF, and hemoglobin (Hb), in each sample was detected using a prototype HGF-TS and an Hb-TS. In addition, the concentrations of HGF and Hb were also determined in each sample is necessary HGF concentrations in oral rinses showed significant correlations with clinical parameters of periodontitis. The positive rate and read value on HGF-TS showed significantly high values in cases of severe periodontitis compared to healthy subjects. Hb-TS showed generally higher positive rates than HGF-TS; however, it showed false positive results in healthy subjects. The concentration of HGF in oral rinses showed close association with the severity of periodontitis, suggesting that the prototype HGF-TS has potential for use in the diagnosis of periodontitis, although further refinement of the test strip is required to increase the sensitivity.

The Effects of Ultraviolet Light-Emitting Diodes with Different Wavelengths on Periodontopathic Bacteria In Vitro.

Objective: The aim of this study was to examine effects of recently developed ultraviolet light-emitting diodes (UV LEDs) wavelengths on in vitro growth and gene expression of cultural periodontopathic bacteria, and on viability of experimental gingival fibroblasts. Materials and methods: Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, and Streptococcus oralis were irradiated by UV LEDs (265, 285, 310, 365, and 448 nm) at 600 mJ/cm2 and grown anaerobically in vitro. The colony forming units were counted after 1 week. Cell morphology was observed using a scanning electron microscope (SEM). Quantitative real-time polymerase chain reaction was performed to investigate gene expression changes by 310 nm irradiation. Viability of the irradiated human gingival fibroblasts was evaluated using WST-8 assay. Results: Both 265 and 285 nm resulted in the complete death of bacteria and fibroblasts, whereas 310 nm caused partial killing and suppression of bacterial growth and much less damage to the fibroblasts in vitro. Both 365 and 448 nm resulted in no significant change. SEM showed that P. gingivalis cells gradually degraded from day 2 or 3 and were severely destructed on day 5 for 265, 285, and 310 nm. The 310 nm irradiation transiently suppressed the transcripts of SOS response- and cell division-relative genes. Conclusions: Both 265 and 285 nm may induce powerful bactericidal effects and severe fibroblast phototoxicity, and 310 nm may induce partial killing or growth suppression of bacterial cells with much less fibroblast phototoxicity. UV lights may have potential for bacterial suppression, with situations dependent on wavelength, in periodontal and peri-implant therapy.

Biological effects of Er:YAG laser irradiation on the proliferation of primary human gingival fibroblasts.

We investigated the biological effects of Er:YAG laser (2940-nm; DELight, HOYA ConBio, Fremont, California) irradiation at fluences of 3.6, 4.2, 4.9, 6.3, 8.1 or 9.7 J cm-2 at 20 or 30 Hz for 20 or 30 seconds on primary human gingival fibroblasts (HGFs). Irradiation at 6.3 J cm-2 promoted maximal cell proliferation, determined by WST-8 assay and crystal violet staining, but was accompanied by lactate dehydrogenase release, on day 3 post-irradiation. Elevation of ATP level, Ki67 staining, and cyclin-A2 mRNA expression confirmed that Er:YAG affected the cell cycle and increased the number of proliferating cells. Transmission electron microscopy showed alterations of mitochondria and ribosomal endoplasmic reticulum (ER) at 3 hours post-irradiation at 6.3 J cm-2 , and the changes subsided after 24 hours, suggesting transient cellular injury. Microarray analysis revealed up-regulation of 21 genes involved in heat-related biological responses and ER-associated degradation. The mRNA expression of heat shock protein 70 family was increased, as validated by Real-time PCR. Surface temperature measurement confirmed that 6.3 J cm-2 generated heat (40.9°C post-irradiation). Treatment with 40°C-warmed medium increased proliferation. Laser-induced proliferation was suppressed by inhibition of thermosensory transient receptor potential channels. Thus, despite causing transient cellular damage, Er:YAG laser irradiation at 6.3 J cm-2 strongly potentiated HGF proliferation via photo-thermal stress, suggesting potential wound-healing benefit.

MicroRNA profiling in gingival crevicular fluid of periodontitis-a pilot study.

Periodontitis is a chronic inflammatory disease that affects the interface of teeth and surrounding tissues. Gingival crevicular fluid (GCF) is an exudate of the periodontal tissues and can be collected from the gap between the tooth and gum (gingival sulcus or periodontal pocket) with paper strips. Testing of GCF is a low-cost and minimally invasive procedure. In a variety of diseases, microRNAs (miRNAs) in body fluids are implicated in pathogenesis, and are suggested as potential diagnostic biomarkers. Here, we profiled miRNAs in GCF (two chronic periodontitis, one aggressive periodontitis, and five healthy subjects) using miRCURY LNA™ Universal RT microRNA PCR System, which yielded quantitative measures of more than 600 miRNAs. Through this analysis, we found that miRNA profiles in GCF of periodontitis patients are distinct from those of healthy controls. We further selected 40 miRNAs and confirmed their differential expression patterns in different subjects (five chronic periodontitis, one aggressive periodontitis, and six healthy subjects) using a custom miRNA PCR panel. This is the first demonstration of miRNA profiling in GCF and its alteration in periodontitis. Our findings suggest that a subset of miRNAs in GCF holds potential as a biomarker for periodontitis.